Open doors without touching round knobs with your hands. This is a simple design and quick fix for typical architectural door knobs. Use a tiewrap to tighten on doorknob. There are two models. S- for knobs under 2" diameter / M - for knobs over 2" diameter. We recommend 100% infill for print settings. Feel free to download, modify and make recommendations. We are working on a 2.0 version with better door support structure. also a 3.0 version that does not need tie-wraps. Parallel to this we are working on a pull version too.